This work was written by Master T'an-kuang of the T'ang dynasty，who was fairly active till around 785 C.E. However，his definite dates were uncertain.
It consists of twenty-two dialogues entitled "Ta- cheng erh-shih-erh `wen` 大乘二十二問 "，or "The twenty-two dialogues on `Mahayana` Buddhism". The questions were put to him by a king of Tibet on various aspects of both Theravada and `Mahayana` Buddhism，such as Buddha nature，`dharmakaya`, `nirvana`，`sunyata`，bodhicitta, `alayavijnana` , `bhutatathata`，the difference of attainment of `nirvana` between a `sravaka` and a bodhisattva and so forth. As a guide to these dialogues, we have classified them into seven sub-divisions:
I. The practices of a Bodhisattva--This consists of six questions：No. 1，2，9，10, 12 and 13. II. The religious cultivation of the ordinary people--This consists of four questions：No. 3，4，8 and 14. III. The various differences among the three `yanas` --This consists of four questions: No. 15，16，17 and 18. IV. The accomplishments of the Buddha--This consists of three questions：No. 5，6，and 7. V. The `dharmakaya` and `nirvana` --This consists of three questions：No.11，19 and 20. VI. The `alayavijnapa` and perfect wisdom--This consists of one question：No.21. VII. The development of Buddhist schools--This consists of one question：No.22.
The present version was edited and collated on the basis of three imperfect and fragmentary manuscripts bearing No. S2674 from the British Museum，London，and Nos. P2690 and P2674 from the `Bibliotheque` Nationale，Paris. There are nearly 400 footnotes explaining the various readings, errors, omissions, corrections and other aspects of the manuscripts.
There is an editorial 'Preface' featuring a brief assessment of the quality，nature，contents, history and other areas of the text. It is hoped that one may be enabled to better understand its importance in Buddhist studies.
